Filtration device for cigarettes

ABSTRACT

A cigarette comprising a filtration device interposed between the tobacco and the mouth of the user. The filtration device includes a wall of impervious material extending transversely to the general direction of movement of the tobacco smoke and a circumferential wall positioned generally rearwardly of the transverse wall. The transverse wall has a plurality of circumferentially spaced openings adjacent the circumferential wall. Each opening has its axis at an angle to the axis of the transverse wall and extending toward the circumferential wall. Each opening converges in a direction toward the circumferential wall.

United States Patent [72] Inventors Peter E. Brudy 224 California Ave; Otto H. Brudy, 559 Askin Blvd.; Joseph E. J. llabowsky, 3015 Sandwich St. West, Apt. 505. all of Windsor. Ontario. Canada [21] Appl. No. 704,333 [22] Filed Feb. 9, I968 [45] Patented July 6, 1971 [54] FILTRATION DEVICE FOR CIGARETTES 4 Claims, 9 Drawing Figs.

[52] U.S.Cl 131/261, l31/l0.5,l3l/210 [51] lnt.Cl A24fl3/04, A24dl/04 [50] FieldolSearch 131/103,

[56] References Cited UNITED STATES PATENTS 1,594,606 8/1926 Clivio 131/201 X 3,394,707 7/1968 Ellis 131/10.5

732,252 6/1903 Assman 13l/10.5 X 2,815,760 12/1957 Schrevs et al.. 131/262 3,373,750 3/1968 Beam 131/105 3,395,713 8/1968 Ent-Keller..... 131/105 X 3,438,381 4/1969 l-lale 13l/l0.5 X

FOREIGN PATENTS 982,670 2/1965 Great Britain 13 l/10.5

6,502,444 8/1966 Netherlands 13 1/105 Primary Examiner-Melvin D. Rein Attorney-Barnes, Kisselle, Raisch and Choate PATENTEUJUL 6|97| 590,827

sum 1 or 2 INVENTORS V PE ER E. BRODY OTTO H. BQUDV seoH LJJMvQOWSKV fimw, KM MPM ATTORNEYS PAIENTEU JUL 6 |97l SHEET 2 OF 2 PIC-11.8

INVENTQRE:

Baum H- Laney BY J SEPH E-J. HAM S Y M M M ATTORNEYS FILTRATION DEVICE FOR CIGARET'IES This invention relates to filtration devices for cigarettes. Although it is suitable for cigarette holding devices, it is primarily intended for incorporation into cigarettes at the time of manufacture.

In recent years, scientifically based findings have been made that link the smoking of cigarettes to numerous health disor ders. Although the nicotine contained in cigarettes has been under attack for some time, only recently has the imminent danger posed by the tars been recognized. Consequently, since the denicotinizing of raw tobaccos is obviously insufficient, the need for a less dangerous cigarette as led to the use of filtration devices.

These tars, the result of combustion of tobacco, are known to be, as a mixture, approximately 40 times as carcinogenic as any one of the numerous components. As well, these tars are known to destroy ciliated tissue which serves to protect the human respiratory system, as well as contributing to the destruction of lung tissue. This breakdown of tissue leaves the human system vulnerable to such diseases as chronic bronchitis and its vicious brother, emphysema. Needless to say, a cigarette is required that is capable of giving the pleasure of tobacco taste without the serious threat presented by inhalation of these tarry substances.

Many filtering devices have been previously proposed, although none has met all of the requirements which the user demands. Some of the more prominent disadvantages which previous devices have had are severe diminution of taste; highpressure drop which results in drawing difficulty, known as hard-draw; difficulties and high cost in their manufacture; excessive weight; and an inability to be adjusted to provide the most desirable combination of all these other features.

The most prominent drawback in prior devices has been a severe dimunition of the tobacco taste. This is a common result of the removal of the particles from the smoke. This is, however, very unsatisfactory to the smoker.

In addition, many prior devices require a pressure drop on the order of to inches of water, in the filter itself. The practical limit is approximately 3 to 3.5 inches, the latter generally being considered unacceptable. The cigarette in its entirety should have a maximum pressure drop of 5.5 to 6.0 inches.

Among the objects of the present invention are to provide a filtering device which will efficiently remove the detrimental substances from the tobacco smoke, which has a low-pressure drop resulting in an easy draw, which is relatively simple and inexpensive to manufacture, which does not substantially increase the total weight of the cigarette, which can be readily modified to vary the retention of the detrimental substances and which does not significantly. affect the tobacco taste or the distinguishable taste of a particular tobacco blend.

In the drawings:

FIG. 1 is a fragmentary part sectional view on a greatly enlarged scale of a cigarette embodying the invention.

FIG. 2 is a longitudinal sectional view of a modified form of the filtration device.

FIG. 3 is a partly diagrammatic fragmentary sectional view on an enlarged scale of the device shown in FIG. 2.

FIG. 4 is a longitudinal sectional view on an enlarged scale ofa further modified form of the filtration device.

FIG. 5 is a partly diagrammatic fragmentary sectional view on an enlarged scale of a portion of the device shown in FIG. 4.

FIG. 6 is a longitudinal sectional view on an enlarged scale ofa further modified form of the filtration device.

. FIG. 7 is a partly diagrammatic fragmentary sectional view on an enlarged scale of a portion of the device shown in FIG.

FIG. 8 is a longitudinal sectional view on an enlarged scale ofa further modified form of the filtration device.

FIG. 9 is a plan view ofa further modified form of the filtration device.

In describing the principle by which the present invention functions in all of its various embodiments, reference is made to FIG. I.

Referring to FIG. I, the filtration device 10 is shown as applied to a cigarette II by being encased by the mouthpiece I2 so that it is interposed between the tobacco l3 and the mouth of the user. As shown in FIG. 1, the filtering device 10 comprises a cylinder I4 and a transverse wall 15 at a right angle to the wall 14. The transverse wall 15 is made ofa preferably thin material, with a thickness on the order of 0.01 5 inches or less, such as aluminum foil. The foil is provided with a plurality of circumferentially spaced openings 16 formed in a suitable manner such as piercing, punching, molding or the like, adjacent the surface 17 of the circumferential wall 14. The openings 16 are positioned toward the wall 14 and have their axes at an angle to the flat transverse wall 15, preferably on the order of 5 to 55. The openings 16 also converge in the direction away from the tobacco and toward the mouthpiece; that is, toward the surface 17.

The size of the openings or perforations at the small end are on the order of 0.005 to 0.045 inches. The center of each opening 16 at the small end is preferably between 0.005 and 0.060 inches from the surface I7 ofwall I4.

When the cigarette is lighted and the smoker draws the smoke towards his mouth, the smoke passes through the openings I6 and is gradually compressed by the tapered surfaces of the openings I6 and is impinged upon the surface 17 of the wall 14. In this fashion the smoke is accelerated in its travel and the detrimental particles in the smoke are deposited on the surface 17 and the gases pass on to the mouth of the user. The particles deposited are in the form of tars and the like and serve to produce an adhesive surface on the surface of surface 17 of the wall 14 which not only facilitates deposit of further particles but also provides an aromating of the passing smoke gases. The greater the accumulation on the surface 17 the more efficient the filtration becomes due to this adhesive action. This can be proven by smoking several cigarettes through a holder in which the device is incorporated.

Essentially, the smoke follows the herein described path as it travels from the tobacco to the mouth of the smoker. As the smoke enters the filtration device 10, it is gradually compressed as it flows through the restrictive openings 16 of the transverse wall 15. After this compression, which effects a considerable acceleration upon the smoke, an impingement of the smoke against the surface 17 of the peripheral wall I4 takes place. If this surface I7 is slightly roughened in texture or treated with adhesive during the manufacturing process, the depositing of materials due to the impingement will be greatly enhanced. Treated or not, this surface will collect a considerable quantity of tarry matter with the first puff on the cigarette, producing an adhesive surface which will provide for more efficient collection during subsequent puffs. The trapped materials remain on the wall surface 17 and the smoke gases which subsequently pass over this residue are aromated with the flavor characteristics of the particles. Consequently, the gases which pass onto the mouth of the smoker have a flavor which is identical to the smoke when particulated; the only difference is a noticeable mildness caused by removal of the generally irritating smoke particles. The openings 16 in the transverse wall 15 approach the peripheral wall 14 at an angle, and subsequently provide an angular" type of impingement which is significantly lower in pressure drop than direct or straight on types of impingement.

In the form of the invention shown in FIGS. 2 and 3, the filtering device 20 is made from a single piece plastic element such as polyethylene having a cylindrical wall 21 and a transverse wall 22 in which the openings 23, corresponding to the openings 16 in FIG. I are formed. FIG. 3 shows the bottom portion of the device shown in FIG. 2 on a greatly enlarged scale.

The filtration device 25 shown in FIGS. 4 and 5 comprises a cylindrical wall 26 and an arcuate transverse wall 27 which has an outer convex surface 28 adjacent to the mouth of the user and an opposite concave surface 29. Circumferentially spaced openings 30 which are positioned at a distance comparable to the device shown in FIG. I from the surface 31 circumferentially in the wall are tapered toward the wall in the same manner as the previously described filtrationdevice The angle that the axes of the openings 30 forms with a diametral plane is within the same range as the angle of the openings 16 in FIG. I to the transverse wall 15, namely, 5 to 55.

in the form of the invention shown in FIGS. 6 and 7, the filtration device 35 comprises a cylindrical wall 36, and a transverse wall 37 at a right angle to the wall 36. in this form an integral extension 38 is positioned centrally of the device 35 and extends in the direction toward the mouth of the user to define a cylindrical surface 39. The openings 40 in the wall 37 are tapered and of a size as is in the previous form of the invention and at an angle to the wall 37 as in the previous form of the invention except that they extend radially inwardly to impinge the smoke against the surface 39.

in the form of the invention shown in FIG. 8, the filtration device 45 has a transverse wall 46 with openings 47 therein and a frustoconical projection 48 that has a surface 49 at an angle less than 90 to the transverse wall 46 against which the smoke is impinged.

in FIG. 9, the axes of the openings 23 are directed circumferentially generally radially as shown in order to provide a spiral action which serves to increase the area on which the impingement may take place.

An important feature of the device embodying the invention is the fact that it may be controlled in all of its features. More specifically, the retention of materials, the pressure drop of the device, the level of taste yielded by the device, and numerous other basic requirements of an acceptable filtration device can be accurately determined by the controlled variation of the component sections of the device, such as the size of openings, the spacing of the openings, the number of openings, the axial length of the openings, the angulation of the openings, the circumferential inclination of the openings and numerous other specifications such as materials and surface finishes.

The following is a description of the basic effects certain modifications would have on a standard basic unit of the following specifications:

I Equidistant.

The number of holes directly affects the overall pressure drop of the device when all other features remain the same. The more openings there are the lower the pressure drop, but the efficiency also decreases with the lower pressure requirement.

it is usually preferable to space the openings equally since the greatest advantage of wall area is available in this manner.

The size of the perforations or openings has a direct bearing upon efficiency and pressure drop, with the prime size usually yielding the lowest pressure dropwith the highest possible retention. However, in some instances, a lower pressure drop is desireable as is a lower efficiency. I

The degree of taper also directly affects the pressure drop and the retention, although not drastically.

The length of the perforations is very important since it combines with the wall spacing to provide proper impingement. This length must be at least 0.005 inches, and so usually rises out from the bulk flatness of the transverse wall.

The thickness of the transverse wall is unimportant as long as it does not affect the length of the. perforation. it has its importance in the control ofthe weight ofthe device.

The angle between the axes of the openings and the transverse wall, the angle of the transverse wall to the peripheral wall and the subsequent angular relationship of the opening to the impingement surface greatly affect the retention, the pressure drop, the aromation of the passing gases and especially the ease of fabrication.

The most radical efiects per degree of change are accomplished by the variation of the circumferential inclination of the openings. Taste, draw, retention all vary drastically with only minor changes in this angle. However, it is not so critical that manufacturing requires especially rigid quality control. With an overall range of 360 a minor variation would be on the order of 5 to 10".

We claim:

1. in a filtration device for use with cigarettes, between the tobacco and the mouth of the user, said device being adapted to be encased within the mouthpiece of a cigarette, the combination comprising a transverse wall of impervious material,

means for supporting said wall so that it extends generally transversely with respect to the general direction of the movement of the tobacco smoke from the tobacco to the mouth of the user,

a circumferential peripheral wall positioned generally rearwardly of the transverse wall and extending generally axially toward the mouth of the user,

said transverse wall having a plurality of circumferentially spaced openings therein adjacent the circumferential axially extending wall,

each said opening having its axis at an angle to the axis of the peripheral wall and extending toward the peripheral wall,

each said opening having sidewalls converging in a direction toward the peripheral wall,

said transverse wall being generally flat and forms an angle of to the circumferential wall.

2. The combination set forth in claim 1 wherein the axes of said openings are inclined circumferentially to produce a spiral action of the smoke passing therethrough.

3. in a filtration device for use with cigarettes, between the tobacco and the mouth of the user, said device being adapted to be encased within the mouthpiece of a cigarette, the combination comprising,

a transverse wall of impervious material,

means for supporting said wall so that it extends generally transversely with respect to the general direction of the movement of the tobacco smoke from the tobacco to the mouth of the user,

a circumferential peripheral wall positioned generally rearwardly of the transverse wall and extending generally axially toward the mouth of the user,

said transverse wall having a plurality of circumferentially spaced openings therein adjacent the circumferential axially extending wall,

each said opening having its axis at an acute angle to the axis of the peripheral wall and extending toward the peripheral wall,

each said opening having sidewalls converging in a direction toward the peripheral wall,

the axes of said openings are inclined circumferentially to produce a spiral action of the smoke passing therethrough.

4. The combination set forth in claim 1 wherein said circumferential wall surrounds said transverse wall and the axes of the openings extend outwardly toward said wall. 

2. The combination set forth in claim 1 wherein the axes of said openings are inclined circumferentially to produce a spiral action of the smoke passing therethrough.
 3. In a filtration device for use with cigarettes, between the tobacco and the mouth of the user, said device being adapted to be encased within the mouthpiece of a cigarette, the combination comprising, a transverse wall of impervious material, means for supporting said wall so that it extends generally transversely with respect to the general direction of the movement of the tobacco smoke from the tobacco to the mouth of the user, a circumferential peripheral wall positiOned generally rearwardly of the transverse wall and extending generally axially toward the mouth of the user, said transverse wall having a plurality of circumferentially spaced openings therein adjacent the circumferential axially extending wall, each said opening having its axis at an acute angle to the axis of the peripheral wall and extending toward the peripheral wall, each said opening having sidewalls converging in a direction toward the peripheral wall, the axes of said openings are inclined circumferentially to produce a spiral action of the smoke passing therethrough.
 4. The combination set forth in claim 1 wherein said circumferential wall surrounds said transverse wall and the axes of the openings extend outwardly toward said wall. 